15-digit Nixie clock contains mostly non-useful information

[Jarek Lupinski] is at it again, this time building a clock using 15 Nixie tubes. Just look at the time…. wait, how do you read this now? It’s not seconds since the epoch, but an homage to a very expensive New York City art piece. [Jarek] took his inspiration from the Metronome art installation in Union Square.

We hadn’t heard of it before and were shocked to learn that this art was commissioned at $4.2 million. It belches steam and confuses passersby with its cryptic fifteen digits. It seems that the eight digits on the left mark the current time – two digits for hours, two for minutes, two for seconds, and the final digit for hundreths of a second. The seven remaining digits count down the time left in the day. So when you watch it, you see the significant digits of the display increasing, and the insignificant half decreasing.

The Nixie version rests snuggly on a 15″x4″ PCB. We’re sure it doesn’t number in the millions, but that couldn’t have been cheap to have manufactured. Each tube has its own driver chip, removing the need for multiplexing. An ATmega168 controls the clock (along with some shift registers to expand the I/O count), reading time from a DS1307 RTC chip. It looks fancy, but where’s the belching smoke on this version?

There are a couple of board houses (Advanced Circuits) which sell a predetermined size of PCB, and you can dimension it and fill it with as many circuits as you like. In addition to this, I got 12 completely different circuits on the same board, and it all costs ~100.